Display device including means for providing signals to a panel drive integrated circuit

Abstract

The present invention provides a display device including a means for providing a signal to a panel driving integrated circuit. A technique of providing a signal to a panel driving integrated circuit, i.e., a panel driving IC, is disclosed. By controlling a capacitance connected to a transmission line, a plurality of signals having different characteristics are stably provided to the panel driving IC according to a display operation or a touch operation.

Description

Technical Field

[0001] This disclosure relates to a technique for stably providing a panel driver integrated circuit with a signal for outputting image data or for sensing touch or proximity. Background Technology

[0002] The screen of an electronic device can be both an area for displaying images and an area for receiving input. Touch sensing technology that recognizes the touch or proximity of external objects enables the screen of the electronic device to receive input. The touch panel within the electronic device is positioned in the same location as the display panel on a flat surface. Therefore, the user can input user manipulation signals to the touch panel while viewing an image on the display panel. Compared to other existing user manipulation input schemes (e.g., mouse-based or keyboard-based input schemes), the method of generating user manipulation signals offers remarkably intuitive results.

[0003] In an in-cell structure where the display panel and touch panel are arranged in the same location, panel driver integrated circuits (ICs), such as source driver ICs, source readout ICs, and gate driver ICs, can drive each panel by transmitting a signal with a constant level over time or a signal with a level that changes over time to the display panel and touch panel. Here, the signal with a constant level can be provided in direct current (DC), and the signal with a level that changes over time can have a periodicity.

[0004] In an in-cell architecture, a common electrode can be used in parallel as both a display panel and a touch panel. If the common electrode is used as a display panel to display image data, the panel driver IC can supply a direct current (DC) voltage to the common electrode. Conversely, if the common electrode is used as a touch panel to sense the touch or proximity of an external object, the panel driver IC can supply a periodic voltage to the common electrode.

[0005] The panel driver IC can receive DC or modulated voltage from an external source and supply it to the panel. To stably supply the DC voltage required for display operation to the panel driver IC, capacitors may need to be connected to the transmission lines. Increasing the capacitance further eliminates the influence of noise on the DC voltage, thus preventing DC voltage fluctuations. Noise may be generated due to poor patterning of pixels or touch electrodes or switching performed by multiplexers.

[0006] To reliably supply the modulation voltage required for touch operation to the panel driver IC, it may be necessary to remove capacitors from the transmission lines. As the capacitance decreases, the modulation voltage varies rapidly between multiple levels, and therefore the response time of the modulation voltage becomes faster. Thus, depending on whether the panel is performing display or touch operation, the display device may need to transmit DC voltage or modulation voltage to the panel driver IC at appropriate timing.

[0007] As mentioned above, if the capacitance in the wires supplying DC voltage or modulation voltage is extremely high or extremely low, neither the DC voltage nor the modulation voltage will be properly transmitted to the panel driver IC. If the capacitance is extremely high, the level of the signal transmitted along the wire can be maintained constantly; this level can be positive for DC voltage and negative for modulation voltage.

[0008] In this regard, embodiments of the present disclosure may provide a technique for stably supplying both DC voltage and modulation voltage to a panel driver IC to suit display operation and touch sensing operation. Summary of the Invention

[0009] In the background art, an aspect of this disclosure is to provide a technique for connecting a capacitor element that provides capacitance to or removing a capacitor element from a transmission line to transmit a direct current (DC) voltage or a modulated voltage to a panel driver integrated circuit (IC).

[0010] Another aspect of this disclosure is to provide a technique for receiving a drive voltage from a power management integrated circuit (IC) and generating and providing a DC voltage or a modulated voltage according to a display operation or a touch operation.

[0011] Another aspect of the embodiments is to provide a technique associated with a signal stabilization circuit, which includes a capacitor element and a switching circuit for controlling the connection and disconnection of the capacitor element.

[0012] According to an aspect of this disclosure, a display device is provided, comprising: a modulation integrated circuit, i.e., a modulation IC, configured to output a direct current voltage, i.e., a DC voltage or a modulation voltage having multiple levels; and a capacitor element configured to be connected to an output terminal of the modulation IC when the DC voltage is output from the modulation IC, and configured to be disconnected from the output terminal of the modulation IC when the modulation voltage is output from the modulation IC.

[0013] The display device may also include a switching circuit disposed between the output terminal of the modulation IC and the capacitor element.

[0014] Control signals for the switching circuit can be received from a timing controller for outputting image data to the panel or from a microcontroller for sensing the touch or proximity of an external object to the panel.

[0015] The switching circuit can be configured to connect the capacitive element to the output of the modulation IC during a first interval of output image data, and can be configured to disconnect the capacitive element from the output of the modulation IC during a second interval of sensing the touch or proximity of an external object.

[0016] The DC voltage can be provided to the common electrode to output image data, and the modulated voltage can be provided to the common electrode to sense the touch or proximity of an external object.

[0017] The common electrode includes a first common electrode and a second common electrode, the first common electrode being used to receive the modulation voltage, the second common electrode being used to receive the modulation voltage and transmit a response signal including information associated with the sensing of touch or proximity to an external object, and the modulation voltage being provided to the first common electrode as a zero-load drive voltage.

[0018] The modulation voltage can be provided to the gate line via a gate driver IC, which is used to scan pixels to output image data.

[0019] The common electrode can be connected to an integrator that senses changes in the capacitance of the common electrode, and the modulation voltage can be provided to the common electrode via the integrator.

[0020] The common electrode can be connected to an integrator that senses changes in the capacitance of the common electrode, and the DC voltage can be supplied to the common electrode by bypassing the integrator.

[0021] The display device may further include a panel driver integrated circuit, i.e., a panel driver IC, configured to drive a panel. The panel driver IC may be configured to operate according to a time-division signal associated with a display interval and a touch interval, in which image data is output to the panel during the display interval, and in which an external object touches or approaches the panel during the touch interval. The modulation IC may be configured to provide the DC voltage to the panel driver IC during the display interval and the modulation voltage to the panel driver IC during the touch interval, according to the time-division signal.

[0022] The panel driver IC may also include a switching circuit disposed between the output terminal of the modulation IC and the capacitor element.

[0023] The panel driver IC can be configured to control the switching circuit according to the time-division signal.

[0024] According to an aspect of this disclosure, a display device is provided, comprising: a modulation integrated circuit, i.e., a modulation IC, configured to receive a direct current voltage, i.e., a DC voltage, and output the DC voltage or a modulation voltage having multiple levels; and a capacitor element connected to an input terminal of the modulation IC and configured to be additionally connected to an output terminal of the modulation IC when the DC voltage is output from the modulation IC, and to be disconnected from the output terminal of the modulation IC when the modulation voltage is output from the modulation IC.

[0025] The display device may further include a switching circuit disposed between the input and output terminals of the modulation IC and configured to control the connection of the capacitor element according to a switching control signal for determining the connection and disconnection between the capacitor element and the output terminal of the modulation IC.

[0026] The switching circuit can be configured to connect the capacitive element to the output of the modulation IC during a first interval of outputting image data, and disconnect the capacitive element from the output of the modulation IC during a second interval of sensing the touch or proximity of an external object.

[0027] The display device may further include a power management integrated circuit, i.e., a power management IC, which is configured to receive power supplied via a first terminal and supply the DC voltage to the modulation IC via a second terminal.

[0028] According to an aspect of this disclosure, a display device is provided, comprising: a modulation integrated circuit, i.e., a modulation IC, configured to receive a direct current voltage, i.e., a DC voltage, and output the DC voltage or a modulation voltage having multiple levels; and a capacitor element configured to be connected to an output terminal of the modulation IC when the DC voltage is output from the modulation IC, and disconnected from the output terminal of the modulation IC when the modulation voltage is output from the modulation IC, wherein the modulation IC includes a switching circuit configured to control the connection of the capacitor element according to a switching control signal for determining whether the capacitor element is connected or disconnected from the output terminal of the modulation IC.

[0029] The capacitor element can be arranged outside the modulation IC.

[0030] The switching circuit can be configured to connect the capacitive element to the output of the modulation IC during a first interval of outputting image data, and disconnect the capacitive element from the output of the modulation IC during a second interval of sensing the touch or proximity of an external object.

[0031] As described above, according to the embodiments, multiple signals with different characteristics, such as time-invariant signals and time-varying signals, can be stably provided to the panel driver IC according to display operations or touch operations.

[0032] According to an embodiment, the influence of noise on multiple signals with different characteristics can be eliminated by controlling the capacitor connected to the transmission line. Attached Figure Description

[0033] Figure 1 This is a diagram illustrating the configuration of a display device according to an embodiment of the present disclosure;

[0034] Figure 2 This is a diagram illustrating the generation and transmission of drive voltage in a power management integrated circuit (IC) according to embodiments of the present disclosure, and the generation and transmission of common electrode voltage, gate low voltage, and gate high voltage in a modulation integrated circuit (IC).

[0035] Figure 3 This is a diagram illustrating a time-invariant DC voltage in a display interval and a time-varying modulation voltage in a touch interval according to an embodiment of the present disclosure;

[0036] Figure 4 This is a diagram illustrating a first configuration of a signal providing apparatus including a signal stabilization circuit according to an embodiment of the present disclosure;

[0037] Figure 5 This is a diagram illustrating a second configuration of a signal providing apparatus including a signal stabilization circuit according to an embodiment of the present disclosure;

[0038] Figure 6 This is a diagram illustrating the process of transmitting a time-invariant DC voltage and a time-varying modulated voltage to a panel according to an embodiment of the present disclosure;

[0039] Figure 7 This is a diagram illustrating a zero-load drive voltage provided to a panel according to an embodiment of the present disclosure;

[0040] Figure 8 This is a diagram illustrating the zero-load drive voltage of the drive touch electrode according to an embodiment of the present disclosure;

[0041] Figure 9 This is a diagram illustrating the configuration of a signal providing device including a signal stabilization circuit according to another embodiment of the present disclosure;

[0042] Figure 10 This is a diagram illustrating the configuration of a signal providing device including a signal stabilization circuit according to another embodiment of the present disclosure; and

[0043] Figure 11This is a diagram illustrating the configuration of a signal providing device including a signal stabilization circuit according to another embodiment of the present disclosure. Detailed Implementation

[0044] Figure 1 This is a diagram illustrating the configuration of a display device.

[0045] Reference Figure 1 The display device 100 may include a panel 110, a source readout IC (SRIC) 120, a gate driver IC (GDIC) 130, a modulation IC (MOD IC) 140, a timing controller (TCON) 150, a microcontroller (MCU) 160, and a power management IC (PMIC) 170.

[0046] In panel 110, multiple data lines (DL) and multiple gate lines (GL) can be arranged, and multiple pixels can be arranged. A pixel may include multiple sub-pixels (SP). Here, a sub-pixel may be red (R), green (G), blue (B), white (W), etc. A single pixel may include RGB sub-pixels (SP), RGBG sub-pixels (SP), RGBW sub-pixels (SP), etc. In the following text, for ease of description, a single pixel is illustrated as including RGB sub-pixels (SP).

[0047] The source readout IC 120, gate driver IC 130, and timing controller 150 may be devices for receiving, generating, and transmitting signals to display an image on the panel 110. The source readout IC 120 and microcontroller 160 may be devices for receiving, generating, and transmitting signals for sensing touch input to the panel 110.

[0048] The source readout IC 120 may include a source driver IC (SDIC). The source driver IC can provide a data voltage (Vdata) to the sub-pixel (SP) via a data line (DL). The data voltage (Vdata) provided via the data line (DL) can be supplied to the sub-pixel (SP) according to the gate drive signal (SCAN).

[0049] Furthermore, the source readout IC 120 may include a readout IC (ROIC). The readout IC, together with the source driver IC, can be included in the source readout IC 120. The readout IC can drive the touch electrode (TE) adjacent to the sub-pixel (SP) and can sense touch input. Here, the common electrode used for display operation can be used as the touch electrode (TE), and the readout IC can provide a common voltage (VCOM) to the common electrode. The readout IC can receive the common voltage (VCOM) from the modulation IC 140. The source readout IC 120 can use a touch line (TL) to drive the touch electrode (TE) and can receive analog signals from the touch electrode (TE).

[0050] Here, if the source readout IC 120 provides a data voltage (Vdata) via the source driver IC, the modulation IC 140 can generate a common voltage (VCOM) with time-invariant characteristics and provided in DC form. During the display interval, the DC common voltage (VCOM) can be provided to the touch electrode (TE). Furthermore, if the source readout IC 120 senses the touch electrode (TE) via the readout IC, the modulation IC 140 can generate a common voltage (VCOM) with periodic and time-varying characteristics. A periodic common voltage (VCOM) can be provided to the touch electrode (TE) during the touch interval.

[0051] The source readout IC 120 can be connected to the bonding pads of the panel 110 in a tape-on-board (TAB) or chip-on-glass (COG) manner. It can be directly disposed on the panel 110 or integrated with the panel 110 according to the embodiment. In addition, the source readout IC 120 can be implemented in a chip-on-film (COF) manner.

[0052] The gate driver IC 130 can provide a gate drive signal (SCAN) with either an on or off voltage via the gate line (GL). If the on-voltage gate drive signal is provided to the sub-pixel (SP), the sub-pixel (SP) is connected to the data line (DL). If the off-voltage gate drive signal (SCAN) is provided to the sub-pixel (SP), the connection between the sub-pixel (SP) and the data line (DL) is disconnected.

[0053] The modulation IC 140 can provide a DC voltage or a modulation voltage to the panel driver IC. Here, the panel driver IC can drive sub-pixels (SPs) to display image data (RGB). The panel driver IC may include a gate driver IC and a source driver IC. Furthermore, the panel driver IC can drive touch electrodes (TEs) to sense the touch or proximity of external objects. Therefore, the panel driver IC may include a readout IC. Additionally, the panel driver IC may include a source readout IC, which includes both a source driver IC and a readout IC.

[0054] DC voltage can be used to drive the sub-pixels (SPs) in the panel driver IC. The DC voltage can be a time-invariant voltage that maintains a level with a constant magnitude or within a predetermined range. Conversely, modulation voltage can be used to drive the touch electrodes (TEs) in the panel driver IC. Modulation voltage can be a time-varying voltage. Modulation voltage can be an alternating current (AC) voltage. AC voltage can include a pulsed voltage with at least one pulse, a periodic voltage with a period greater than or equal to 1, or a sinusoidal voltage that continuously varies between multiple levels.

[0055] The common voltage (VCOM) is the voltage transmitted to the source readout IC 120. The common voltage can be a time-invariant DC voltage during the display intervals in which the display device 100 outputs image data (RGB), and it can also be a time-varying modulated voltage during the touch intervals in which the display device 100 senses the touch or proximity of an external object. The modulation IC 140 can receive a drive voltage (VLT) from the power management IC 170. The modulation IC 140 can convert the drive voltage (VLT) into a time-invariant common voltage (VCOM) during the display intervals, or it can convert the drive voltage (VLT) into a time-varying common voltage (VCOM) during the touch intervals. Optionally, the drive voltage (VLT) can be provided in DC form, and therefore the modulation IC 140 can fully utilize the drive voltage (VLT) as a time-invariant common voltage (VCOM) during the display intervals.

[0056] The gate high voltage (VGH) and gate low voltage (VGL) can be a time-invariant DC voltage or a time-varying modulated voltage transmitted to the gate driver IC 130. The gate driver IC 130 can generate a gate drive signal (SCAN) from the gate high voltage (VGH) and gate low voltage (VGL). For example, the gate driver IC 130 can generate pulses by alternately combining the high voltage level of the time-invariant gate high voltage (VGH) and the low voltage level of the time-invariant gate low voltage (VGL), and can use the generated pulses as the gate drive signal (SCAN). The modulator IC 140 can receive a drive voltage (VLT) from the power management IC 170. The modulator IC 140 can convert the drive voltage (VLT) into a time-invariant gate high voltage (VGH) and a time-invariant gate low voltage (VGL), or it can convert the drive voltage (VLT) into a time-varying gate high voltage (VGH) and a time-varying gate low voltage (VGL). Alternatively, the drive voltage (VLT) can be provided in DC form, and thus the modulation IC 140 can use the drive voltage (VLT) as a time-invariant gate high voltage (VGH) and a time-invariant gate low voltage (VGL).

[0057] Furthermore, the modulation IC 140 can generate a zero-load drive (ZLD) voltage and transmit it to the source readout IC 120 and the gate driver IC 130 to reduce the impact of the touch sensor's parasitic capacitance on the sensing results. The zero-load drive voltage (ZLD) can have the same phase and amplitude as the touch drive voltage driving the touch sensor. If the zero-load drive voltage (ZLD) is provided across the parasitic capacitor along with the touch drive voltage, the amount of charge charged on the parasitic capacitor can be zero, and thus the parasitic capacitance can be removed.

[0058] For example, if a common voltage (VCOM) is used as the touch drive voltage to drive the touch sensor (i.e., the touch electrode (TE)), the zero-load drive voltage (ZLD) can have the same phase and amplitude as the common voltage (VCOM). Therefore, the modulation IC 140 can transmit the zero-load drive (ZLD) voltage to the gate driver IC 130, and the gate driver IC 130 can transmit the zero-load drive (ZLD) voltage to the panel 110 via the gate line (GL).

[0059] The timing controller 150 can provide control signals to the gate driver IC 130 and the microcontroller 160. For example, the timing controller 150 can transmit a gate control signal to start scanning to the gate driver IC 130. The timing controller 150 can output image data (RGB) to the microcontroller 160. Furthermore, the timing controller 150 can transmit a data control signal (DCS) to the microcontroller 160, which controls the source readout IC 120 to provide a data voltage (Vdata) to each sub-pixel (SP). Additionally, the timing controller 140 can transmit a touch control signal (TCS) to the microcontroller 160, which controls the source readout IC 120 to drive the touch electrode of each sub-pixel (SP) to sense touch input.

[0060] Microcontroller 160 can transmit or receive data with source readout IC 120. Microcontroller 160 can transmit control data for controlling source readout IC 120, as well as a clock for synchronizing data and image data (RGB) provided to panel 110, to source readout IC 120. Source readout IC 120 can generate sensing data by sensing the touch or proximity of an external object via a touch sensor, and can transmit the sensing data to microcontroller 160.

[0061] The microcontroller 160 and the source readout IC 120 can communicate using either a Serial Peripheral Interface (SPI) scheme or an Internal Integrated Circuit (I2C) scheme. In either SPI or I2C, the communication entity can operate as both a master and a slave device. Specifically, the microcontroller 160 can operate as a master device, and the source readout IC 120 can operate as a slave device. There can be multiple source readout ICs 120, and each source readout IC 120 can function as a slave device of the microcontroller 160.

[0062] The power management IC 170 can provide power to the panel 110, source readout IC 120, gate driver IC 130, modulation IC 140, timing controller 150, and microcontroller 160. The power management IC 170 can provide power by transmitting a power supply voltage (PWR) via power lines. Power supply voltages (PWR) with different values ​​can be supplied to the corresponding circuits. The power supply voltage (PWR) can be processed to have voltage and current suitable for the operation of each circuit, and the processed power supply voltage (PWR) can be supplied to the corresponding circuit. The power management IC 170 can be used as a power supply source for the internal circuitry of the display device 100.

[0063] Furthermore, the power management IC 170 can provide a drive voltage (VLT) to the modulation IC 140. The power management IC 170 can receive power supplied via a first terminal and can generate the drive voltage (VLT) and supply it to the modulation IC 140 via a second terminal. The modulation IC 140 can generate a DC voltage or a modulation voltage by converting the drive voltage (VLT) and can transmit the DC voltage or modulation voltage to the source readout IC 120 and the gate driver IC 130. The drive voltage (VLT) and DC voltage can have time-invariant characteristics. Conversely, the modulation voltage can have time-varying characteristics. Furthermore, the drive voltage (VLT) can be provided in DC form, and therefore the modulation IC 140 can use the drive voltage (VLT) entirely as a DC voltage.

[0064] Figure 2 This is a diagram illustrating the generation and transmission of drive voltage in a power management circuit according to an embodiment of the present disclosure, and the generation and transmission of common electrode voltage, gate low voltage, and gate high voltage in a modulation circuit.

[0065] Reference Figure 2 This illustrates the process of generating a common electrode voltage (VCOM), a gate low voltage (VGL), and a gate high voltage (VGH) from drive voltages (VLT1, VLT2, and VLT3).

[0066] The power management IC 170 may include a first power management IC (PMIC_1) 171, a second power management IC (PMIC_2) 172, and a third power management IC (PMIC_3) 173 to generate drive voltages (VLT1, VLT2, VLT3) with different characteristics. These drive voltages can have different voltage levels. The drive voltages (VLT1, VLT2, and VLT3) generated by different power management ICs and possessing different characteristics can be converted by the modulation IC 140 into different types of modulation voltages, such as common electrode voltage (VCOM), gate low voltage (VGL), and gate high voltage (VGH).

[0067] The modulation IC 140 may include a first modulation IC (MOD_1) 141, a second modulation IC (MOD_2) 142, and a third modulation IC (MOD_3) 143 to generate a common electrode voltage (VCOM), a gate low voltage (VGL), and a gate high voltage (VGH). Here, the generated voltages can have different voltage levels and different phases depending on the purpose. The common voltage (VCOM) can be transmitted to the source readout IC to drive the touch electrode (TE) in the display interval and touch interval. The gate high voltage (VGH) and gate low voltage (VGL) can be transmitted to the gate driver IC to be used as scan signals for connecting pixels and data lines.

[0068] For example, a first power management IC 171 can generate a first drive voltage (VLT1) and transmit it to a first modulation IC 141. The first modulation IC 141 can be a circuit for generating a common voltage (VCOM) and can convert the first drive voltage (VLT1) to the common voltage (VCOM). Optionally, the first modulation IC 141 can use the first drive voltage (VLT1) provided in DC form entirely as the common voltage (VCOM). Furthermore, a second power management IC 172 can generate a second drive voltage (VLT2) and transmit it to the second modulation IC 142. The second modulation IC 142 can be a circuit for generating a gate high voltage (VGH) and can convert the second drive voltage (VLT2) to the gate high voltage (VGH). Optionally, the second modulation IC 142 can use the second drive voltage (VLT2) provided in DC form entirely as the gate high voltage (VGH). Furthermore, a third power management IC 173 can generate a third drive voltage (VLT3) and transmit it to the third modulation IC 143. The third modulation IC 143 may be a circuit for generating a gate low voltage (VGL) and may convert a third drive voltage (VLT3) into a gate low voltage (VGL). Optionally, the third modulation IC 143 may use the third drive voltage (VLT3) provided in DC form as the gate low voltage (VGL).

[0069] Here, the first to third drive voltages (VLT1, VLT2, and VLT3) can have time-invariant characteristics. Conversely, the common electrode voltage (VCOM), gate low voltage (VGL), and gate high voltage (VGH) can have time-invariant or time-varying characteristics. If a voltage has time-invariant characteristics, it can be considered to have a level of a predetermined amplitude or a level within a predetermined range, independent of time. Therefore, a DC voltage can have time-invariant characteristics. If a voltage has time-varying characteristics, it can be considered to have a level that changes with time. Therefore, an alternating current (AC) voltage, such as a pulsed voltage or a periodic voltage, can have time-varying characteristics.

[0070] Therefore, the modulation IC 140 can convert the first to third drive voltages (VLT1, VLT2, and VLT3) having time-invariant characteristics into time-invariant or time-varying voltages as needed. Optionally, the modulation IC 140 can use the first to third drive voltages (VLT1, VLT2, and VLT3) having time-invariant characteristics entirely as time-invariant voltages. Desiredly, the modulation IC 140 can generate time-invariant voltages such as DC voltages during display intervals when image data is displayed on the panel, and can generate time-varying voltages such as modulation voltages during touch intervals when sensing the touch or proximity of an external object.

[0071] Figure 3 This is a diagram illustrating a time-invariant DC voltage in a display interval and a time-varying modulation voltage in a touch interval according to an embodiment of the present disclosure.

[0072] Reference Figure 3 The modulation IC can generate DC voltage or modulation voltage according to the display interval and the touch interval. The modulation IC can generate a time-invariant DC voltage during the display interval and supply it to the panel driver IC, and it can generate a time-varying modulation voltage during the touch interval and supply it to the panel driver IC. Here, the time-varying modulation voltage can include pulse voltage, periodic voltage, or alternating current (AC) voltage.

[0073] According to embodiments of this disclosure, a time-division signal (TSYNC) can determine the timing and duration of the display interval and touch interval, respectively. The time-division signal (TSYNC) can be the vertical synchronization signal or the horizontal synchronization signal itself, or it can be a signal derived from it. Therefore, the time-division signal (TSYNC) can be generated primarily from a timing controller, but is not limited thereto, and can be generated from a microcontroller or a source readout IC. In the figures, "display" represents the display interval, and "touch" represents the touch interval.

[0074] Based on the time-division multiplexing (TSYNC) signal, the display device can output image data during display intervals and sense the touch or proximity of external objects during touch intervals. The panel can output image data during display intervals and sense the touch or proximity of external objects during touch intervals, and therefore the panel driver IC, such as the gate driver IC and source readout IC, can receive DC voltage or modulation voltage from the modulation IC according to each interval. The modulation IC can transmit a DC voltage with time-invariant characteristics to the panel driver IC during display intervals and a modulation voltage with time-varying characteristics to the panel driver IC during touch intervals.

[0075] For example, the source sense IC can receive a DC common voltage (VCOM_DC) to be passed to the common electrode during the display interval. The source sense IC can also receive a modulated common voltage (VCOM_M) to be passed to the common electrode during the touch interval. The modulated common voltage (VCOM_M) can be a signal whose voltage amplitude varies between low and high levels. The DC common voltage (VCOM_DC) can be a signal whose voltage amplitude is constantly maintained at an intermediate level between low and high levels.

[0076] Similarly, the gate driver IC can receive a DC gate high voltage (VGH_DC) during the display interval. The gate driver IC can also receive a modulated gate high voltage (VGH_M) to be supplied to the panel via the gate line during the touch interval. The modulated gate high voltage (VGH_M) can be a signal whose voltage amplitude varies between low and high levels. The DC gate high voltage (VGH_DC) can be a signal whose voltage amplitude is constantly maintained at an intermediate level between low and high levels.

[0077] Furthermore, the gate driver IC can receive a DC gate low voltage (VGL_DC) during the display interval. The gate driver IC can also receive a modulated gate low voltage (VGL_M) to be supplied to the panel via the gate line during the touch interval. The modulated gate low voltage (VGL_M) can be a signal whose voltage amplitude varies between low and high levels. The DC gate low voltage (VGL_DC) can be a signal whose voltage amplitude is constantly maintained at an intermediate level between low and high levels.

[0078] Figure 4 This is a diagram illustrating a first configuration of a signal providing apparatus including a signal stabilization circuit according to an embodiment of the present disclosure.

[0079] Reference Figure 4The signal providing device 400 according to the embodiment may include a modulation IC 140, a timing controller 150, a power management IC 170, and a signal stabilization circuit 410. The signal stabilization circuit 410 can stabilize the DC voltage or modulation voltage output from the modulation IC 140.

[0080] The power management IC 170 can provide a drive voltage to the modulation IC 140. The drive voltage can be converted into a DC voltage or a modulated voltage by the modulation IC 140. Optionally, the drive voltage can be used entirely as a DC voltage by the modulation IC 140.

[0081] For example, if the first power management IC 171 provides a first drive voltage (VLT1) to the first modulation IC 141, the first modulation IC 141 can convert the first drive voltage (VLT1) into a common voltage (VCOM), such as a DC common voltage or a modulated common voltage.

[0082] Modulation IC 140 can provide DC voltage or modulation voltage to panel driver IC 210. The DC voltage can be provided by panel driver IC 210 to the pixel electrodes of the panel, and the modulation voltage can be provided by panel driver IC 210 to the touch sensors of the panel, such as touch electrodes. Modulation IC 140 can generate a time-invariant voltage during the display interval and a time-varying voltage during the touch interval. For example, first modulation IC 141 can generate and output a DC common voltage during the display interval and can generate and output a modulated common voltage during the touch interval.

[0083] The signal stabilization circuit 410 may include a switching circuit 411 and a capacitor. The switching circuit 411 may be positioned between the capacitor and the output of the modulation IC 140, and the capacitor may be connected to or disconnected from the output of the modulation IC 140. The capacitor can be used to stably supply DC voltage or modulation voltage to the panel driver IC 210. The signal stabilization circuit 410 may connect the capacitor to the output of the modulation IC 140, or disconnect it from the output depending on the DC voltage or modulation voltage.

[0084] For example, if the modulation IC 140 provides a DC common voltage to the panel driver IC 210 during a display interval, the switching circuit 411 can connect a capacitor (Cs) to the output of the modulation IC 140. The capacitor (Cs) increases the capacitance in the transmission lines and helps maintain a constant DC common voltage level unaffected by noise. The DC common voltage level remains unchanged. Alternatively, if the modulation IC 140 provides a modulation common voltage to the panel driver IC 210 during a touch interval, the switching circuit 411 can disconnect the capacitor (Cs) from the output of the modulation IC 140. Disconnecting the capacitor (Cs) reduces the capacitance, and therefore the modulation common voltage can change its level quickly. This can improve the response speed to changes in the modulation common voltage level.

[0085] The signal stabilization circuit 410 can receive a switch control signal (CTR) for controlling the opening and closing of the switch circuit 411. The timing controller 150 can generate the switch control signal (CTR). A time-division signal (TSYNC) or a signal derived from a time-division signal (TSYNC) can be used as the switch control signal (CTR). The switch circuit 411 can connect or disconnect the capacitor (Cs) according to the display interval and touch interval defined by the switch control signal (CTR).

[0086] Figure 5 This is a diagram illustrating a second configuration of a signal providing device including a signal stabilization circuit according to an embodiment of the present disclosure.

[0087] Reference Figure 5 According to the embodiment, the signal providing device 400 can receive a switch control signal (CTR) from a circuit other than a timing controller.

[0088] For example, microcontroller 160 can generate a switch control signal (CTR) and transmit it to signal stabilization circuit 410. Alternatively, the switch control signal (CTR) can be generated from power management IC 170 or panel driver IC 210 and transmitted to signal stabilization circuit 410. The source driver IC, readout IC, and source readout IC in panel driver IC 210 can generate the switch control signal (CTR). Here, the switch control signal (CTR) can be generated from a time-division multiplexing (TSYNC) signal or a signal derived from a time-division multiplexing (TSYNC) signal.

[0089] Figure 6 This is a diagram illustrating the process of transmitting a time-invariant direct current (DC) voltage and a time-varying modulated voltage to a panel according to an embodiment of the present disclosure.

[0090] Reference Figure 6DC voltage or modulation voltage can be transmitted to panel 110 via panel driver IC. The process by which time-invariant DC voltage reaches panel 110 and the process by which time-varying modulation voltage reaches panel 110 can be different from each other. Time-invariant DC voltage and time-varying modulation voltage can be used for different purposes. Hereinafter, the process by which common voltage (VCOM) reaches the touch electrode (TE) of panel 110 via source readout circuit 120 is described as an example.

[0091] For example, a common voltage (VCOM) can be used in both the display interval and the touch interval. The modulation IC can provide the common voltage (VCOM) to the source readout IC 120. The modulation IC can generate and provide a DC common voltage with time-invariant characteristics in the display interval, and can generate and provide a modulated common voltage with time-varying characteristics in the touch interval.

[0092] In the display interval, a common voltage (VCOM), i.e., a DC common voltage, can be input to the analog front end of the source readout IC 120. The first switching device (SW1) of the source readout IC 120 can be short-circuited, and the second switching device (SW2) can be open. The DC common voltage can be input to the touch electrode (TE) along the first switching device (SW1). The touch electrode (TE) can be used as a common electrode in the display interval and can output image data based on the voltage difference between the data voltage and the DC common voltage supplied to the touch electrode (TE).

[0093] During the touch interval, a common voltage (VCOM), i.e., a modulated common voltage, can also be input to the analog front end of the source sense IC 120. The first switching device (SW1) of the source sense IC 120 can be open, and the second switching device (SW2) can be short-circuited. The modulated common voltage can be supplied along the second switching device (SW2) to a terminal of the amplifier (BF) and simultaneously to the touch electrode (TE). An integrator 610, including the amplifier (BF) and a capacitor (Ci), can receive a response signal from the touch electrode (TE) in response to the modulated common voltage and can generate sensing data. The sensing data can include information associated with the touch or proximity of an external object.

[0094] Figure 7 This is a diagram illustrating the operation of a zero-load drive voltage provided to a panel according to an embodiment of the present disclosure.

[0095] Reference Figure 7The modulation IC 140 can generate a modulation voltage as a zero-load drive voltage (ZLD). To improve the sensing sensitivity associated with touch or proximity to an external object 10, it is necessary to reduce the influence of parasitic capacitance around the touch electrode (TE). This parasitic capacitance can be reduced by providing a voltage equal to the touch drive voltage of the touch electrode (TE) to the wires around the touch electrode (TE). A voltage equal to the touch drive signal (TE) of the touch electrode can be understood as a zero-load drive voltage.

[0096] During the touch interval, modulation IC 140 can receive a drive voltage (VLT) from power management IC 170, generate a modulation common voltage (VCOM_M) from the drive voltage (VLT), and provide the modulation common voltage to source readout IC 120. Here, capacitors (Cs) can stabilize the modulation common voltage (VCOM_M) without being connected to the output of modulation IC 140. If the modulation common voltage (VCOM_M) reaches a point with a fast output response, it can be understood as stable. Source readout IC 120 can provide the modulation common voltage (VCOM_M) to the touch electrode (TE) via the touch line (TL).

[0097] Modulation IC 140 provides a zero-load drive voltage (ZLD) to source readout IC 120, which is the same signal as the modulation common voltage (VCOM_M). Source readout IC 120 provides a zero-load drive voltage (ZLD) to sub-pixels (SPs) via data lines (DL). Simultaneously, modulation IC 140 provides a zero-load drive voltage (ZLD) to gate driver IC 130. Gate driver IC 130 provides a zero-load drive voltage ZLD to sub-pixels SPs via gate lines (GL). The zero-load drive voltage ZLD on data lines (DL) and gate lines (GL) reduces parasitic capacitance around the touch electrode TE.

[0098] Figure 8 This is a diagram illustrating the zero-load drive voltage of the drive touch electrode according to an embodiment of the present disclosure.

[0099] Reference Figure 8 The source readout IC 120 can provide a modulation voltage and a zero-load drive voltage (ZLD) to the touch electrode (TE) during the touch interval. The modulation IC of the signal providing device can generate the modulation voltage and the zero-load drive voltage (ZLD) and provide them to the source readout IC 120. Here, the connection between the capacitor (Cs) and the output of the modulation IC can be disconnected.

[0100] The source readout IC 120 can provide a modulated common voltage (VCOM_M) to the touch electrode (TE) and can sense changes in capacitance that occur upon touch or proximity of an external object 10. In the figure, the touch electrode (TE) where the external object 10 is located can be shaded.

[0101] Simultaneously, to reduce the impact of surrounding parasitic capacitance, the source readout IC 120 can provide a zero-load drive voltage (ZLD) to the surrounding touch electrode (TE), which is beyond the influence of the external object 10. The zero-load drive voltage (ZLD) provided to the surrounding touch electrode (TE) can be a signal with characteristics similar to the modulation common voltage (VCOM_M), and thus can suppress the occurrence of parasitic capacitance. Additionally, the zero-load drive voltage (ZLD) provided to the gate line and data line can also remove parasitic capacitance generated between the touch electrode (TE) and the gate line and data line.

[0102] Figure 9 This is a diagram illustrating the configuration of a signal providing device including a signal stabilization circuit according to another embodiment of the present disclosure.

[0103] Reference Figure 9 The document describes a signal providing apparatus 900 according to another embodiment. A switching circuit 911 of a signal stabilizing circuit 910 may be arranged between the input and output terminals of a modulation IC 140. A first terminal of the switching circuit 911 is connected to the input terminal of the modulation IC 140, and a second terminal of the switching circuit 911 may be connected to the output terminal of the modulation IC 140. A capacitor (Cs) may be connected to the input terminal of the modulation IC 140 together with the first terminal of the switching IC 911.

[0104] If the modulation IC 140 generates and outputs a time-invariant DC voltage, the switching circuit 911 can connect a capacitor (Cs) to the output of the modulation IC 140. If the modulation IC 140 generates and outputs a time-varying modulation voltage, the switching circuit 911 can disconnect the capacitor (Cs) from the output of the modulation IC 140. Here, a time-invariant DC voltage can be generated during the display interval, and a time-varying modulation voltage can be generated during the touch interval. The switching circuit 911 can connect or disconnect the capacitor (Cs) to suit the timing of the display interval and the touch interval. A switch control signal (CTR) can determine the timing of the display interval and the touch interval, and the switching circuit 911 can receive the switch control signal (CTR) and operate according to a time-division scheme. The switch control signal (CTR) can be generated from, but is not limited to, the timing controller 150, and can be generated from a microcontroller, a power management IC, a source driver IC, a readout IC, or a source readout IC.

[0105] If the switching circuit 911 of the signal stabilization circuit 910 connects the capacitor (Cs) to the output of the modulation IC 140, the switching circuit 911 can provide a bypass for the drive voltage output by the power management IC 170. The drive voltage provided in DC form can be directly input to the panel driver IC 210 via the switching circuit 911. Alternatively, the DC voltage generated by the modulation IC 140 can be input to the panel driver IC 210.

[0106] For example, in a display interval, the first power management IC 171 can provide a first drive voltage (VLT1) in DC form to the modulation IC 140. The first modulation IC 141 can generate a time-invariant common voltage (VCOM), such as a DC common voltage, from the first drive voltage (VLT1) and can provide this time-invariant common voltage to the panel driver IC 210. Optionally, the first modulation IC 141 can use the first drive voltage (VLT1) as the time-invariant common voltage (VCOM). The switching circuit 911 can connect a capacitor (Cs) to the output of the modulation IC 140 according to a switch control signal (CTR). The first drive voltage (VLT1) can flow along the switching circuit 911 to the panel driver IC 210. The capacitor (Cs) can provide high capacitance and thus help to stably provide the first drive voltage (VLT1) or the time-invariant common voltage (VCOM), such as a DC common voltage, to the panel driver IC 210.

[0107] During the touch interval, the first power management IC 171 can provide a first drive voltage (VLT1) in DC form to the modulation IC 140. The first modulation IC 141 can generate a time-varying common voltage (VCOM), such as a modulated common voltage, from the first drive voltage (VLT1) and can provide this time-varying common voltage to the panel driver IC 210. The switching circuit 911 can disconnect the capacitor (Cs) from the output of the modulation IC 140 according to the switch control signal (CTR). The first drive voltage (VLT1) may not flow along the switching circuit 911 to the panel driver IC 210. The switching circuit 911 can disconnect the capacitor (Cs), i.e., remove the capacitor, and can help to stably provide the time-varying common voltage (VCOM) (e.g., the modulated common voltage) to the panel driver IC 210.

[0108] Figure 10 This is a diagram illustrating the configuration of a signal providing device including a signal stabilization circuit according to another embodiment of the present disclosure.

[0109] Reference Figure 10The document describes a signal providing device 1000 according to another embodiment. A switching circuit 1011 of the signal stabilization circuit may be included in a modulation IC 1040. The switching circuit 1011 may be arranged inside the modulation IC 1040, but it can still be connected to the output of the modulation IC 1040.

[0110] Conversely, the capacitors (Cs) can be placed outside the modulation IC 1040. However, the capacitors (Cs) can still be connected to the output of the modulation IC 1040 via the switching circuit 1011. In the figure, the capacitors (Cs) can be placed outside the modulation IC 1040, but are not limited to this, and can be placed inside the modulation IC 1040 according to the design.

[0111] According to another embodiment, the signal providing device 1000 can also generate a time-invariant DC voltage or a time-varying modulation voltage, and can supply the time-invariant DC voltage or the time-varying modulation voltage to the panel driver IC 210. For example, if the first power management IC 171 provides a first drive voltage (VLT1) to the first modulation IC 141, the first modulation IC 141 can generate a common voltage (VCOM) from the first drive voltage (VLT1). Optionally, the first modulation IC 141 can use the first drive voltage (VLT1) provided in DC form as the common voltage (VCOM). Here, the first drive voltage (VLT1) can be a time-invariant DC voltage. The common voltage (VCOM) can be a time-invariant DC voltage or a time-varying modulation voltage. The first modulation IC 141 can generate a DC common voltage in the display interval and can generate a modulated common voltage in the touch interval.

[0112] Figure 11 This is a diagram illustrating the configuration of a signal providing device including a signal stabilization circuit according to another embodiment of the present disclosure.

[0113] Reference Figure 11 The document describes a signal providing device 1100 according to another embodiment. A switching circuit 1111 of the signal stabilization circuit may be included in the panel driver IC 1110. The switching circuit 1111 may be arranged inside the panel driver IC 1110, but the switching circuit 1111 can still be connected to the output of the modulation IC 140.

[0114] Conversely, the capacitors (Cs) can be placed outside the panel driver IC 1110. However, the capacitors (Cs) can still be connected to the output of the modulation IC 140 via the switching circuit 1111. In the figure, the capacitors (Cs) can be placed outside the panel driver IC 1110, but are not limited to this, and can be placed inside the panel driver IC 1110 depending on the design.

[0115] According to another embodiment, the signal providing device 1100 can also generate a time-invariant DC voltage or a time-varying modulation voltage, and can supply the time-invariant DC voltage or the time-varying modulation voltage to the panel driver IC 1110. For example, if the first power management IC 171 provides a first drive voltage (VLT1) to the first modulation IC 141, the first modulation IC 141 can generate a common voltage (VCOM) from the first drive voltage (VLT1). Optionally, the first modulation IC 141 can use the first drive voltage (VLT1) provided in DC form as the common voltage (VCOM). Here, the first drive voltage (VLT1) can be a time-invariant DC voltage. The common voltage (VCOM) can be a time-invariant DC voltage or a time-varying modulation voltage. The first modulation IC 141 can generate a DC common voltage in the display interval and can generate a modulated common voltage in the touch interval.

[0116] Cross-references to related applications

[0117] This application claims priority to Korean Patent Application No. 10-2020-0060661, filed on May 21, 2020, the entire contents of which are incorporated herein by reference.

Claims

1. A display device, comprising: A modulation integrated circuit, or modulation IC, is configured to receive a direct current voltage (DC voltage) and output the DC voltage or a modulated voltage having multiple levels. A switching circuit is arranged between the input terminal and the output terminal of the modulation IC; as well as A capacitor element is configured to be connected to the input terminal of the modulation IC and configured to be disconnected from the output terminal of the modulation IC by controlling the switching circuit when the modulation voltage is output from the modulation IC.

2. The display device according to claim 1, wherein, The capacitor element is configured to be connected to the output terminal of the modulation IC by controlling the switching circuit when the DC voltage is output from the modulation IC.

3. The display device according to claim 2, wherein, The switching circuit receives control signals from a timing controller that outputs image data to the panel or from a microcontroller that senses the touch or proximity of an external object to the panel.

4. The display device according to claim 2, wherein, The switching circuit is configured to connect the capacitive element to the output of the modulation IC during a first interval of outputting image data, and is configured to disconnect the capacitive element from the output of the modulation IC during a second interval of sensing the touch or proximity of an external object.

5. The display device according to claim 1, wherein, The DC voltage is provided to the common electrode to output image data, and the modulated voltage is provided to the common electrode to sense the touch or proximity of an external object.

6. The display device according to claim 5, wherein, The common electrode includes a first common electrode and a second common electrode, the first common electrode being used to receive the modulated voltage, and the second common electrode being used to receive the modulated voltage and transmit a response signal including information associated with sensing the touch or proximity of an external object. The modulation voltage is provided to the first common electrode as a zero-load drive voltage.

7. The display device according to claim 6, wherein, The modulation voltage is provided to the gate line via a gate driver IC, which is used to scan pixels to output image data.

8. The display device according to claim 5, wherein, The common electrode is connected to an integrator, which senses changes in the capacitance of the common electrode. The modulation voltage is provided to the common electrode via the integrator.

9. The display device according to claim 5, wherein, The common electrode is connected to an integrator, which senses changes in the capacitance of the common electrode. The DC voltage is supplied to the common electrode by bypassing the integrator.

10. The display device according to claim 1, further comprising a panel driver integrated circuit, i.e., a panel driver IC, configured to drive the panel. in, The panel driver IC is configured to operate according to time-division signals associated with a display interval and a touch interval, wherein image data is output to the panel during the display interval, and external object touches or approaches the panel during the touch interval. The modulation IC is configured to provide the DC voltage to the panel driver IC during the display interval and the modulation voltage to the panel driver IC during the touch interval, based on the time-division signal.

11. A display device, comprising: A modulation integrated circuit, or modulation IC, is configured to receive a direct current voltage (DC voltage) and output the DC voltage or a modulated voltage having multiple levels. as well as A capacitor element is connected to the input terminal of the modulation IC and is configured to be additionally connected to the output terminal of the modulation IC when the DC voltage is output from the modulation IC, and to be disconnected from the output terminal of the modulation IC when the modulation voltage is output from the modulation IC.

12. The display device according to claim 11, further comprising: A switching circuit is arranged between the input and output terminals of the modulation IC and configured to control the connection of the capacitor element according to a switching control signal used to determine the connection and disconnection between the capacitor element and the output terminal of the modulation IC.

13. The display device according to claim 12, wherein, The switching circuit is configured to connect the capacitive element to the output of the modulation IC during a first interval of outputting image data, and to disconnect the capacitive element from the output of the modulation IC during a second interval of sensing the touch or proximity of an external object.

14. The display device according to claim 11, further comprising: A power management integrated circuit, or power management IC, is configured to receive power supplied via a first terminal and to supply the DC voltage to the modulation IC via a second terminal.

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